1. Field
One embodiment of the invention relates to an information processing apparatus and a cooling method for an information processing apparatus.
2. Description of the Related Art
In recent years, personal computers have been implemented with a cooling unit that operates to cool the environment inside the computer housing, responding to a temperature rise inside the computer housing. In addition, the cooling unit may perform cooling operations based on an indirect measured value, such as whether or not the computer is powered by a commercial alternating power source or powered by a battery or a direct temperature measurement represented by a temperature indication number. An example of such a personal computer is disclosed in Japanese Patent Application Publication (KOKAI) No. 9-198166.
A temperature management method described in this reference determines a desired state of at least one cooling option such as a fan on the basis of a detected temperature and an indirect input. For example, a fan speed is set to any of 0%, 50%, 75%, and 100%.
Moreover, personal computers have been implemented with audio visual (also referred as “AV”) functionality. As an example, personal computers may include a TV tuner is incorporated to view a TV program and an MPEG-2 encoder, a hard disk drive (also referred as “HDD”), or a digital versatile disk (also referred as “DVD”) drive is incorporated to compress, encode, and record the TV program in accordance with the MPEG-2 system.
In such an AV viewing environment, the computer is used as an AV device instead of as a personal computer, and thus, a lower noise output by the computer would be preferable. Since it is possible to execute an application in a multi-task manner in a general personal computer use environment, a cooling capability is fulfilled so as to achieve its function even at the time of a maximum load.
Therefore, it is necessary to increase a cooling capability according to an operating load of a system, and the number of rotations of a fan is controlled in a multi-stepped manner. Since the control system is also applied to the AV viewing environment as is, a user recognizes that the number of rotations of the fan changes during viewing of an AV program, and it is expected that the user feels the change to be noisy. Further, if the number of rotations of the fan increases, it leads to noise generation.